Longitudinally expandable plastic bottle, and method and apparatus for manufacturing the same

ABSTRACT

There is proposed and provided a plastic bottle the longitudinal dimension (height) of which is decreased substantially when the bottle is manufactured, as compared with the time when the bottle is filled with contents, a method for manufacturing the plastic bottle, and an apparatus for manufacturing the plastic bottle. When the bottle is manufactured, the bottle being constructed so that a longitudinal part or the whole of the bottle, except a mouth portion at the upper end, has a bellows shape in the horizontal direction, the bottle is molded in a state of having substantially smaller volume and height than the volume and height at the time when the bottle is filled with contents, and when an empty portion is formed in the bottle by an operation of drinking up the contents, the bottle can be made again in a state of having substantially smaller volume and height than the volume and height at the time when the bottle has been filled with contents.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a plastic bottle having a differentheight between a case where it is filled with a liquid such as juice ormineral water and a case where it is empty, a method for manufacturingthe plastic bottle, which mainly uses a blow molding process calledstretch blow or injection blow or generally called PET resin blow, andan apparatus for manufacturing the plastic bottle.

2. Description of the Related Art

In recent years, the volume of production of synthetic resin bottles hasbecome enormous.

A serous drawback of the synthetic resin bottle is that when juice ormineral water in the bottle is drunk up and the bottle is thrown away,the bottle remains in the original shape, and when the emptied bottle isthrown away in a trash container, the trash container is filled soonwith bottles because the state is as if air is thrown away in the trashcontainer, and eventually bottles are thrown away on the road, whichharms the living environment. In addition, the recovery costs foremptied bottles and the labor costs for cleaning put a heavy burden onpublic utilities.

Also, although these synthetic resin bottles can be manufactured by easymeans such as blow forming, the strength thereof is not enough fortransportation on a motor vehicle or other transportation meansaccompanied by heavy vibrations and for piled-up display in a store.

Furthermore, when the bottles are transported from a bottle manufacturerto a company which fills the bottles with juice or mineral water, thebottles take a lot of space, and the state is as if air is transported.Therefore, the ratio of transportation costs to production costs isconsiderably high.

In the above situation, the inventor has proposed a liquid vessel thatis devised so as to be capable of being contracted easily when anemptied liquid vessel is recovered.

This liquid vessel is made of a relatively soft synthetic resin, and theperipheral wall of the liquid vessel having a mouth on the top thereofis formed into a pleated shape (see Patent Document 1).

Also, the inventor has additionally proposed an invention of a vesselthat has a shape such that the volume thereof can be decreasedsubstantially by applying a load to the vessel in the vertical directionand/or the torsional direction, and means for keeping the contractedshape (see Patent Document 2).

According to the proposed inventions, when the vessel is collapsed, theheight of vessel can be decreased and the contracted state can be kept.

As the conventional means for manufacturing plastic bottles, what iscalled the biaxial stretching blow molding process using a preform ismainly used.

For example, an invention has been proposed in which the opening/closingoperation of a pair of molds into which the preform can be charged isperformed by a ring and a rotating disk which are pivotally mounted soas to be rotatable through 180 degrees (see Patent Document 3). However,there has been proposed no invention of a new excellent mold formanufacturing bellows of the vessel and each fold forming the bellowsand a manufacturing method therefor.

An invention is publicly known in which a preform, which is a primaryproduct molded into a predetermined shape, is subjected to biaxialstretching blow molding using a primary blow molding mold to form aprimary intermediate product, the primary intermediate product beingheated to be heat contraction deformed compulsorily into a secondaryintermediate product, and the secondary intermediate product issubjected to secondary blow molding using a secondary blow molding moldto form a bottle or other vessels without being hardly extended ascompared with the primary blow (see Patent Document 4). However, themold and method of this invention are used to obtain a vessel havingheat resistance against very high heat contraction, but needless to say,they are not used to manufacture the before-mentioned vessel having apleated shape.

-   [Patent Document 1] Japanese Patent Laid-Open No. 2001-213418    (abstract)-   [Patent Document 2] Japanese Patent Laid-Open No. 2002-68156    (abstract)-   [Patent Document 3] Japanese Patent Laid-Open No. 11-48327 (pages 3    and 4)-   [Patent Document 4] Japanese Patent No. 2777790 (page 2)

SUMMARY OF THE INVENTION

Generally, an object of the present invention is to propose and providea plastic bottle the longitudinal dimension (height) of which isdecreased substantially when the bottle is manufactured, as comparedwith the time when the bottle is filled with contents, a method formanufacturing the plastic bottle, and an apparatus for manufacturing theplastic bottle.

Another object of the present invention is to propose and provide aplastic bottle in which the normal volume and longitudinal dimensionthereof are provided when the bottle is filled with mineral water orjuice, a method for manufacturing the plastic bottle, and an apparatusfor manufacturing the plastic bottle.

Still another object of the present invention is to propose and providea plastic bottle in which the volume (longitudinal dimension) of thebottle can be made very small when juice or mineral water in the bottleis drunk up and the bottle is thrown away, a method for manufacturingthe plastic bottle, and an apparatus for manufacturing the plasticbottle.

Still another object of the present invention is to propose and providea plastic bottle having a shape such that the bottle is easy to carryand that the bottle does not slip out of fingers even dew condensationoccurs on the surface of bottle, a method for manufacturing the plasticbottle, and an apparatus for manufacturing the plastic bottle. Also,still another object of the present invention is to enable thelongitudinal dimension of an emptied portion of bottle to be decreasedduring the time when the contents in the bottle is drunk.

Still another object of the present invention is to provide a plasticbottle in which the number of bottles capable of being contained in atrash container is increased significantly as compared with theconventional bottle for which an emptied bottle is thrown away withoutdecreasing the longitudinal dimension (height) and the trash containeris filled soon with bottles and cannot contain bottles. By achieving theabove object, a large quantity of empty bottles can be transported atthe same time. Therefore, still another object of the present inventionis to significantly reduce the recovery costs for emptied bottles andthe labor costs for cleaning and recovering.

A mold in accordance with the present invention is suitable formanufacturing the above-described bottle in large quantities, andmoreover can surely form a bellows portion and each fold forming thebellows. As a result, there could be proposed a plastic bottle which cankeep a collapsed state thereof when the bottle is collapsed, and amanufacturing method therefor, and there could be provided an apparatusfor manufacturing the plastic bottle.

A feature of the present invention is a plastic bottle in which when thebottle is manufactured, the bottle being constructed so that alongitudinal part or the whole of the bottle, except a mouth portion atthe upper end, has a bellows shape in the horizontal direction, thebottle is molded in a state of having substantially smaller volume andheight than the volume and height at the time when the bottle is filledwith contents. When such a bottle is transported from a manufacturingplant to a contents charging plant, the longitudinal dimension (height,volume) thereof is substantially decreased, so that the quantity oftransportation can be increased significantly as compared with theconventional plastic bottle.

Also, the plastic bottle in accordance with the present invention iseasy to carry because the outer periphery thereof has a bellows shape,and there is no fear that the bottle slips out of fingers even dewcondensation occurs.

Another feature of the present invention is that when an empty portionis formed in the bottle by an operation of drinking up the contents, thebottle can be made again in a state of having substantially smallervolume and height than the volume and height at the time when the bottlehas been filled with contents.

As a result, even when the contents in the bottle is left undrunk, thebottle can be carried by being put in a bag such as a pocketbook. Also,when the contents are drunk up and the bottle is thrown away, the bottleis collapsed so that the volume and height thereof is significantlydecreased, and then the collapsed bottle can be thrown away in a trashcontainer. Therefore, the trash container can be prevented from beingfilled soon with bottles, and the recovery and transportation work canbe made efficient as compared with the conventional work that is as ifair is transported.

A feature of method for manufacturing a plastic bottle in accordancewith the present invention is a simple method which includes a step ofmolding of the bottle constructed so that a longitudinal part or thewhole of the bottle, except a mouth portion at the upper end, has abellows shape in the horizontal direction, and a step of compressionmolding of the bottle so that the molded bottle is compressed in thelongitudinal direction and the compressed state is kept at ordinarytemperature. By this simple method, the above-described plastic bottlehaving excellent operation and effects can be obtained.

A feature of apparatus for manufacturing a plastic bottle in accordancewith the present invention is a simply constructed apparatus whichincludes a mold for molding the bottle constructed so that alongitudinal part or the whole of the bottle, except a mouth portion atthe upper end, has a bellows shape in the horizontal direction, and acompression molding mechanism for compressing the molded bottle in thelongitudinal direction. By this simply constructed apparatus, theabove-described plastic bottle having excellent operation and effectscan be obtained in a large volume at a low cost.

Another feature of plastic bottle in accordance with the presentinvention is that the bellows shape of the bottle has an upper sidehaving an arcuate shape protruding upward and a lower side having astraight shape. For the plastic bottles having such a feature, it hasbeen found, as a result of repeated experiments, that the collapsedstate can be kept when the bottle is transported or thrown away.

Another feature of the manufacturing method is that in the step ofmolding of the bottle, a preform is automatically fed into the mold, andthe bellows shaped bottle is molded with a high-pressure air of about 40kilogram. By this feature, a bottle can be manufactured in which thereis no fear that the bottle is cracked, broken, or bent even in anexpanding and contracting operation, for example, when the bottle iscontracted for transportation from a molding plant to the contentscharging plant, when the contents are drunk up and the empty portion ofbottle is contracted, or when the bottle is thrown away by beingcollapsed completely.

Another feature of the manufacturing apparatus is that the compressionmolding mechanism, which compression molds the bottle so that unusedplastic bottles are transported in large quantities from the moldingplant to the contents charging plant, best suitably includes a mechanismfor placing the bellows shaped bottle in the longitudinal direction anda mechanism for compressing the bottle in the longitudinal direction,and concretely the bottle is pressed from a bottom portion of the bottletoward the mouth portion by a piston and cylinder mechanism which isoperated by a fluid pressure and is provided on the apparatus body.

Also, another feature of the present invention is that the mechanism forplacing the bellows shaped bottle in the longitudinal direction isprovided, on the apparatus body, with a mechanism for chucking the mouthportion with the mouth portion of the bottle downward.

Further, another feature of the present invention is that in the step ofcompression molding of the bottle, when the molded bottle is compressedin the longitudinal direction to collapse a bellows shaped portion ofthe bottle from one side or both sides in the lengthwise directiontoward the center of the bottle, a state in which the bellows shapedportion is collapsed in a lapped manner can be kept, and that the methodincludes a step of charging contents, in which the bottle in the statein which the bellows shaped portion is collapsed in a lapped manner istransported to the contents charging plant where the bottle is filledwith contents, and air is blown to expand the bottle before the contentsare charged, or the bottle is restored to the original state beforebeing collapsed under a pressure of contents charged. As a result, thequantity of transported bottles and the quantity of bottles contained ina trash container can be increased dramatically because the bottle canbe collapsed, although conventionally, the bottles have been transportedfrom the molding plant to the contents charging plant as if air istransported, the empty bottle has been bulky when being thrown away andthe trash container has been filled soon with bottles, and an absolutequantity of bottles transported to a recycling plant has beenrestricted.

It has been found that the step of compression molding of the bottle isperformed while air in the bottle is sucked, by which the work can beperformed very easily and surely.

The configuration in which the whole shape of the bottle in accordancewith the present invention is selected appropriately from a circularcylinder including an elliptical one, a prism including a quadrangularone, a circular cone and a pyramid including truncated ones, a hourglass dram shape, and a barrel shape, the configuration in which thehorizontally sectional shape of the bottle is appropriately selectedfrom a circle including an ellipse and a quadrangle including arectangle, and the configuration in which the invention can be appliedto manufacturing means for a bottle with a label, on which a trademark,contents of bottle, and the like are printed, put at the outer peripherythereof are thought to be within the technical scope of the presentinvention.

Besides, the present invention has other excellent objects, features,operation, and effects of invention, and these are clarified by thedescription of an embodiment given below.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front view showing the whole of a bottle in accordance withan embodiment;

FIG. 2 is a front view of the bottle shown in FIG. 1 in a collapsedstate;

FIG. 3 is an enlarged sectional view of a bellows portion of the bottleshown in FIG. 1;

FIG. 4 is an enlarged sectional view of a shoulder portion of the bottleshown in FIG. 1;

FIG. 5 is a sectional explanatory view of a mold;

FIG. 6 is a sectional explanatory view of a compression moldingmechanism, showing a state before the bottle is collapsed;

FIG. 7 is a sectional explanatory view showing a state of the bottleafter being collapsed;

FIG. 8 is a piping diagram for a compression molding mechanism;

FIG. 9 is a sectional explanatory view showing a state in which thebottle is being collapsed;

FIG. 10 is a sectional explanatory view of a bellows portion of thebottle;

FIG. 11 is a sectional explanatory view of a bottom portion of thebottle; and

FIG. 12 is an explanatory view of a flow from manufacture to throw-awayof the bottle.

DESCRIPTION OF SYMBOLS

-   (A) Height-   (A)′ Height-   (L)′ Height-   (L) height-   A Cylinder portion-   B Bottom portion-   C Shoulder portion-   d1 Outside diameter-   d2 Outside diameter-   d3 Outside diameter-   h1 Height of upper part of first fold-   h2 Height of lower part of first fold-   1 Bottle-   2 Bellows portion-   3 Mouth portion-   4 Back portion-   5 First bellows portion-   6 Second bellows portion-   7 Third bellows portion-   8 Fourth bellows portion-   9 Curved shape-   10 Protruding arcuate shape-   11 Straight shape-   12 Peak-   13 Valley-   14 Upper surface-   15 Lower surface-   16 Mold-   17 Preform-   18 Compression molding mechanism-   19 Horizontal bed-   20 Chuck mechanism-   21 Pillar-   22 Support rod-   23 Support rod-   24 Cylinder-   25 Piston rod-   26 Pressing member-   27 Pressure source-   28 Piping-   29 Three port connection valve-   30 Appropriate shutoff valve-   31 Piston upper part-   32 Transportation-   33 Cleaning-   34 Sterilizing-   35 Charging-   36 Store-   37 During drinking-   38 About ¼ to {fraction (1/10)}

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

In FIG. 1, reference numeral 1 denotes a bottle obtained by amanufacturing method in accordance with the present invention. Thebottle 1 shown in FIG. 1 is in a state of being removed from a mold 16for molding the bottle 1, that is, in a state in which a height (L)thereof is equivalent to a height in a case where the bottle 1 is filledwith contents.

The bottle 1 shown in FIG. 2 is in a state after the bottle 1 has beenmolded by a compression molding mechanism 18 which compresses the bottle1 in the longitudinal direction, that is, in a state in which the bottle1 has a height (L)′ in an empty state. The height of the bottle 1 canusually be contracted to ½ to {fraction (1/10)} of the height (L)′. Anembodiment of the present invention will now be described with referenceto the accompanying drawings. First, the construction, operation, andeffects of the present invention are explained because this explanationleads to easy understanding of the features of the present invention.

The bottle 1 shown in FIG. 1 is in a state of being removed from a mold,and the outer periphery and inner periphery in the direction of height(L) [length] excluding a mouth portion on the top have a bellows portion2. At this time, the height (L) of the bottle 1 corresponds to a volumeof 500 ml at the time when the bottle 1 is filled with contents.

More specifically, the bottle 1 shown in FIG. 1 has a height of 195 mm,a maximum diameter of 71.5 mm, and a volume of 500 ml, and has a shapehaving 12 folds of the bellows portion 2.

In FIG. 1, reference numeral 3 denotes a mouth portion for drinking, and4 denotes a back portion ranging from the mouth portion 3 to a firstbellows portion 5.

In this embodiment, the outside diameter of the first bellow portion 5is 30.25 mm, and the outside diameter of a second bellows portion 6 is33.95 mm. The inside diameter of a portion between the first bellowsportion 5 and the second bellows portion 6 is 47 mm.

Similarly, the outside diameter of a third bellows portion 7 is 34.85mm, and the inside diameter of a portion between the second bellowsportion 6 and the third bellows portion 7 is 51.1 mm.

Further, in FIG. 9, the outside diameter of a fourth bellows portion 8is 35.75, which is the maximum outside diameter, and the inside diameterof a portion between the third bellows portion 7 and the fourth bellowsportion 8 is 54.5 mm.

The outside diameters of fifth to twelfth bellows portions are the sameas the outside diameter of the fourth bellows portion 8, and the insidediameters of portions between these bellow portions are the same as theinside diameter of a portion between the third bellows portion 7 and thefourth bellows portion 8.

In this case, each fold has a shape like an unidentified flying object(UFO) called an Adamski type, and therefore is divided into upper andlower parts with respect to the horizontal direction.

Referring to FIG. 3, the heights of an upper part h1 and a lower part h2of the fold of the first bellows portion 5 are 6.5 mm and 5.5 mm,respectively, those of the fold of the second bellows portion 6 are 7 mmand 5 mm, respectively, and those of the fold of the third bellowsportion 7 are 8.5 mm and 6.5 mm, respectively.

More specifically, in an example of dimensions of folds of the firstbellows portion 5 to the third bellows portion 7 in FIG. 3, it is animportant point that an upper surface 14 of the UFO shape has a curvedshape 9 of 20 mmR protruding outward in this embodiment, and contrarilya lower surface 15 thereof has a straight shape 11 via a protrudingarcuate shape 10 of 0.8 mmR.

This construction of this embodiment is explained together with theoperation thereof. The bottle 1 in the state shown in FIG. 1 is dividedinto three portions: a cylinder portion A including a central portionand a lower portion, a bottom portion B, and a shoulder portion C asshown in FIG. 9. The portions A and C have two diameters, larger andsmall, so that the bottle 1 keeps a stable vertical state.

Specifically, the inside and outside diameters of the cylinder portion Aincluding the central portion and lower portion are formed by the samefold, and the shoulder portion C is apparently curved in a convex shapeof gentle inclination toward the mouth portion 3. In particular, in theshoulder portion C, as shown in FIG. 4, the inside diameter of a valley13 forming the fold is decreased gradually in the range from the centralportion to the mouth portion 3, and the inclination angle thereof has alarger difference than the cylinder portion A. Therefore, in a state inwhich the central portion is expanded, the inside diameter andinclination angle of a peak 12 and the valley 13 forming the fold cankeep a state in which the height is contracted because of the strengthand elastic force of material even when drinking operation is stoppedduring the time when the contents is drunk, and the bottle 1 iscompressed in the longitudinal direction and the empty portion iscollapsed.

This means that the shoulder portion C and the cylinder portion A of thebottle 1 press the folds of the shoulder portion C that may becontracted by the restoring force thereof, and the end surface of thevalley 13 compresses the valley end surface of the fold locatedadjacently in the vertical direction.

In a state viewed from the apex of the peak 12 of fold at this time, thecompressed state corresponds to a state in which the valleys 13 on bothsides are pushed toward the apex of this peak 12. At this time, thecompression component on a gentle inclination side of the upper surface14 of fold is larger than the compression component on a sharpinclination side of the lower surface 15 because the inclination of theformer compression component is smaller than the inclination of thelatter compression component. Therefore, the valley 13 on the sharpinclination side moves toward the apex of the peak 12.

It can be thought that the bottle 1 undergoes two large changes at thistime.

A first change is such that the inside diameter of the peak 12 formingthe fold is increased by an expansion pressure, or the inside diameterof the valley 13 is decreased by a contraction pressure, and a secondchange is such that a sharp inclination surface of the lower surface 15forming the fold is bent.

Subsequently, the sharp inclination surface passes just under the peak12, and further slips into the inside of the gentle inclination side ofthe upper surface 14. When the height of the bottle 1 is decreased tothe contracted state, a force for restoring the inside diameter of thepeak 12 and the inside diameter of the valley 13 acts, or the bent stateof the lower surface 15 formed by the above operation is restored to anexpanded state, by which a stable state is formed.

Therefore, the contracted state can be kept even if a compressive forceis not always applied.

For the valley 13 having a small inside diameter, the inside diameterthereof is further decreased under a contraction pressure, and acompressive stress is generated.

When the contraction pressure is removed, the stress acts so as to bereleased, and the expanded state is restored.

Therefore, the bottle 1 keeps the contracted state at atmosphericpressure, and when no compressive stress is generated by a difference ininside diameter of the valley 13, the contracted state is kept.

As a result of many experiments, the height (volume) of the bottle 1could be made ¼ to {fraction (1/10)}, and even if the bottle 1 is thrownaway in a trash container, the space for throwing away the bottle 1could be decreased significantly.

EXAMPLES

The following is a description of an example of a mold suitable for massproduction of the bottle 1 in accordance with the present invention.

In FIG. 5, reference numeral 16 denotes a two-piece mold formanufacturing the cylindrical bottle 1 shown in FIG. 1. A preform 17 canbe inserted through the bottom surface of the mold 16.

Explanation is given of a process for manufacturing the bottle 1 usingthe mold 16 in this example. First, the mold 16 is in an opened state.

In this state, the preform 17 is automatically inserted into the mold 16from the downside. Then, after the preform 17 has been heated uniformly,high-pressure air of about 40 kilograms is sent into the preform 17 toexpand the preform 17, by which the bottle 1 is formed.

The bottle 1 thus obtained has a height approximately equal to that atthe time when the bottle 1 is filled with contents such as juice.

In FIG. 6, reference numeral 18 denotes a mechanism for compressionmolding the bottle 1, and 19 denotes a horizontal bed. In a centralportion of the bed 19, although the details are not shown, a chuckmechanism 20 having an appropriate construction is provided. The mouthportion 3 of the bottle 1 is chucked by the chuck mechanism 20 so thatthe bottle 1 can surely be held in a reversed vertical state.

Reference numeral 21 denotes a pair of pillars erected on both sides ofthe chuck mechanism 20. In the intermediate portion and the top endportion of the pillars 21, upper and lower support rods 22 and 23 areprovided to bridge the pillars 21. Reference numeral 24 denotes acylinder fixed vertically between the support rods 22 and 23. A pistonrod 25 of the cylinder 24 penetrates the lower support rod 23, and atthe lower end thereof, a pressing member 26 is provided which engagesslightly with the bottom portion B of the bottle 1 to press the bottomportion B of the bottle 1 toward the mouth portion 3.

A fluid supplied to the cylinder 24 may be any appropriate fluid such asair or oil. Means for supplying the fluid may be selected from publiclyknown means.

For example, in FIG. 8, reference numeral 27 denotes a pressure source.The output of the pressure source 27 is sent to portions above and belowa piston upper part 31 in the cylinder 24 via piping 28, a three portconnection valve 29, and an appropriate shutoff valve 30.

The bottle 1 removed from the mold 16 is set on the chuck mechanism 20of the compression molding mechanism 18.

Next, an appropriate fluid is sent to the portion above the piston upperpart 31 in the cylinder 24 from the pressure source 27 via the piping28. As a result, the piston upper part 31 and the piston rod 25 lower,and the pressing member 26 at the lower end of the piston rod 25 comesinto contact with the bottom portion B of the bottle 1, by which thebottle 1 is compressed. The height of the bottle 1 having a small volume(height), which has been obtained as described above, is contracted toabout ¼ to {fraction (1/10)} of the original height.

As shown in FIGS. 9 to 11, the cylinder portion A including the upperportion and the lower portion of the bottle 1 in this state becomes in astate in which the shoulder portion C and the cylinder portion A arecompressed and contracted. Specifically, the folds in the shoulderportion C are pressed from a state of the bottle 1 which is removed fromthe mold 16 as shown in FIGS. 3 and 4, and the end surface of the valley13 compresses the valley end surface of the fold located adjacently inthe vertical direction.

In a state viewed from the apex of the peak 12 of fold at this time, thecompressed state corresponds to a state in which the valleys 13 on bothsides are pushed toward the apex of this peak 12. At this time, thecompression component on a gentle inclination side of the upper surface14 of fold is larger than the compression component on a sharpinclination side of the lower surface 15, and therefore the valley 13 onthe sharp inclination side moves toward the apex of the peak 12 asdescribed above. Thereupon, in the collapsed bottle 1; a sphere cutshape and the curved shape 9 which form an upper inclination portion offold in the shoulder portion C balance with a lower inclination portionof fold in the cylinder portion A, so that the bottle 1 can be kept inthe collapsed state without a cap being put.

FIG. 12 shows a flow from manufacture to throw-away of the bottle inaccordance with the present invention.

As described above, the bottle 1 in accordance with the presentinvention is molded using the mold 16. In this case, the height (volume)of the bottle 1 is (L) which is the same height as that at the time whenthe bottle 1 is filled with contents. Next, the bottle 1 is transferredto the compression molding mechanism 18, where the bottle 1 iscompressed in the longitudinal direction. Thereby, the bottle (height)is contracted significantly, so that in transportation 32 of the bottle,the quantity of transportation can be increased dramatically as comparedwith the conventional bottle.

Next, the bottle 1 is transported to a contents charging plant, wherecleaning 33 or sterilizing 34 using air pressure etc. is accomplished.When these jobs are not needed, the bottle 1 is expanded before charging35 of contents. After a cap or a label has been put, the bottle 1 isdisplayed and sold in a store 36.

Even during drinking 37 of mineral water or other contents, an emptyportion of the bottle 1 can be compressed to decrease the volume(height) of the bottle 1. Thereby, even the bottle 1 from which some ofcontents has been drunk can easily be thrust into a pocketbook and canbe carried.

After all contents have been drunk up, the empty bottle 1 is collapsedfrom the upside or downside direction or both directions to reduce thevolume of bottle to about ¼ to {fraction (1/10)} (38), and is thrownaway in a trash container, etc. Thereby, the quantity of bottlescontained in the trash container can be increased greatly. Also, in therecovery work, the quantity of recovered bottles can be increasedsignificantly.

1. A longitudinally expandable plastic bottle, in which when said bottleis manufactured, said bottle being constructed so that a longitudinalpart or the whole of said bottle, except a mouth portion at the upperend, has a bellows shape in the horizontal direction, said bottle ismolded in a state of having substantially smaller volume and height thanthe volume and height at the time when said bottle is filled withcontents, and when an empty portion is formed in said bottle by anoperation of drinking up said contents, said bottle can be made again ina state of having substantially smaller volume and height than thevolume and height at the time when said bottle has been filled withcontents.
 2. A method for manufacturing a longitudinally expandableplastic bottle, comprising a step of molding of said bottle constructedso that a longitudinal part or the whole of said bottle, except a mouthportion at the upper end, has a bellows shape in the horizontaldirection, and a step of compression molding of said bottle so that themolded bottle is compressed in the longitudinal direction and thecompressed state is kept at ordinary temperature.
 3. An apparatus formanufacturing a longitudinally expandable plastic bottle, comprising amold for molding said bottle constructed so that a longitudinal part orthe whole of said bottle, except a mouth portion at the upper end, has abellows shape in the horizontal direction, and a compression moldingmechanism for compressing the molded bottle in the longitudinaldirection.
 4. The longitudinally expandable plastic bottle according toclaim 1, wherein the bellows shape of said bottle has an upper sidehaving an arcuate shape protruding upward and a lower side having astraight shape.
 5. The method for manufacturing a longitudinallyexpandable plastic bottle according to claim 2, wherein in forming thebellows shape of said bottle, said bellows shape has an upper sidehaving an arcuate shape protruding upward and a lower side having astraight shape.
 6. The apparatus for manufacturing a longitudinallyexpandable plastic bottle according to claim 3, wherein said mold formolding said bottle has a mold portion for forming said bellows shapehaving an upper side having an arcuate shape protruding upward and alower side having a straight shape.
 7. The method for manufacturing alongitudinally expandable plastic bottle according to claim 2, whereinin the step of molding of said bottle, a preform is automatically fedinto a mold, and the bellows shaped bottle is molded with ahigh-pressure air of about 40 kilogram.
 8. The apparatus formanufacturing a longitudinally expandable plastic bottle according toclaim 3, wherein said compression molding mechanism comprises amechanism for placing the bellows shaped bottle in the longitudinaldirection and a mechanism for compressing said bottle in thelongitudinal direction.
 9. The apparatus for manufacturing alongitudinally expandable plastic bottle according to claim 3, whereinsaid mechanism for placing the bellows shaped bottle in the longitudinaldirection is provided, on the apparatus body, with a mechanism forchucking said mouth portion with the mouth portion of the bottledownward.
 10. The apparatus for manufacturing a longitudinallyexpandable plastic bottle according to claim 3, wherein the mechanismfor compressing said bottle in the longitudinal direction in saidcompression molding mechanism for said bottle is constructed so thatsaid bottle is pressed from a bottom portion of said bottle toward themouth portion by a piston and cylinder mechanism which is operated by afluid pressure and is provided on the apparatus body.
 11. The method formanufacturing a longitudinally expandable plastic bottle according toclaim 2, wherein in the step of compression molding of said bottle, whenthe molded bottle is compressed in the longitudinal direction tocollapse a bellows shaped portion of said bottle from one side or bothsides in the lengthwise direction toward the center of said bottle, astate in which said bellows shaped portion is collapsed in a lappedmanner can be kept.
 12. The method for manufacturing a longitudinallyexpandable plastic bottle according to claim 2, wherein said methodcomprises a step of charging contents, in which said bottle in the statein which said bellows shaped portion is collapsed in a lapped manner istransported to a contents charging plant where said bottle is filledwith contents, and air is blown to expand said bottle before saidcontents are charged, or said bottle is restored to the original statebefore being collapsed under a pressure of contents charged.
 13. Themethod for manufacturing a longitudinally expandable plastic bottleaccording to claim 2, wherein the step of compression molding of saidbottle is performed while air in said bottle is sucked.
 14. The methodfor manufacturing a longitudinally expandable plastic bottle accordingto claim 5, wherein in the step of molding of said bottle, a preform isautomatically fed into a mold, and the bellows shaped bottle is moldedwith a high-pressure air of about 40 kilogram.
 15. The apparatus formanufacturing a longitudinally expandable plastic bottle according toclaim 6, wherein said compression molding mechanism comprises amechanism for placing the bellows shaped bottle in the longitudinaldirection and a mechanism for compressing said bottle in thelongitudinal direction.
 16. The apparatus for manufacturing alongitudinally expandable plastic bottle according to claim 6, whereinsaid mechanism for placing the bellows shaped bottle in the longitudinaldirection is provided, on the apparatus body, with a mechanism forchucking said mouth portion with the mouth portion of the bottledownward.
 17. The apparatus for manufacturing a longitudinallyexpandable plastic bottle according to claim 8, wherein said mechanismfor placing the bellows shaped bottle in the longitudinal direction isprovided, on the apparatus body, with a mechanism for chucking saidmouth portion with the mouth portion of the bottle downward.
 18. Theapparatus for manufacturing a longitudinally expandable plastic bottleaccording to claim 15, wherein said mechanism for placing the bellowsshaped bottle in the longitudinal direction is provided, on theapparatus body, with a mechanism for chucking said mouth portion withthe mouth portion of the bottle downward.
 19. The apparatus formanufacturing a longitudinally expandable plastic bottle according toclaim 6, wherein the mechanism for compressing said bottle in thelongitudinal direction in said compression molding mechanism for saidbottle is constructed so that said bottle is pressed from a bottomportion of said bottle toward the mouth portion by a piston and cylindermechanism which is operated by a fluid pressure and is provided on theapparatus body.
 20. The apparatus for manufacturing a longitudinallyexpandable plastic bottle according to claim 8, wherein the mechanismfor compressing said bottle in the longitudinal direction in saidcompression molding mechanism for said bottle is constructed so thatsaid bottle is pressed from a bottom portion of said bottle toward themouth portion by a piston and cylinder mechanism which is operated by afluid pressure and is provided on the apparatus body.
 21. The apparatusfor manufacturing a longitudinally expandable plastic bottle accordingto claim 15, wherein the mechanism for compressing said bottle in thelongitudinal direction in said compression molding mechanism for saidbottle is constructed so that said bottle is pressed from a bottomportion of said bottle toward the mouth portion by a piston and cylindermechanism which is operated by a fluid pressure and is provided on theapparatus body.
 22. The method for manufacturing a longitudinallyexpandable plastic bottle according to claim 5, wherein in the step ofcompression molding of said bottle, when the molded bottle is compressedin the longitudinal direction to collapse a bellows shaped portion ofsaid bottle from one side or both sides in the lengthwise directiontoward the center of said bottle, a state in which said bellows shapedportion is collapsed in a lapped manner can be kept.
 23. The method formanufacturing a longitudinally expandable plastic bottle according toclaim 7, wherein in the step of compression molding of said bottle, whenthe molded bottle is compressed in the longitudinal direction tocollapse a bellows shaped portion of said bottle from one side or bothsides in the lengthwise direction toward the center of said bottle, astate in which said bellows shaped portion is collapsed in a lappedmanner can be kept.
 24. The method for manufacturing a longitudinallyexpandable plastic bottle according to claim 14, wherein in the step ofcompression molding of said bottle, when the molded bottle is compressedin the longitudinal direction to collapse a bellows shaped portion ofsaid bottle from one side or both sides in the lengthwise directiontoward the center of said bottle, a state in which said bellows shapedportion is collapsed in a lapped manner can be kept.
 25. The method formanufacturing a longitudinally expandable plastic bottle according toclaim 5, wherein said method comprises a step of charging contents, inwhich said bottle in the state in which said bellows shaped portion iscollapsed in a lapped manner is transported to a contents charging plantwhere said bottle is filled with contents, and air is blown to expandsaid bottle before said contents are charged, or said bottle is restoredto the original state before being collapsed under a pressure ofcontents charged.
 26. The method for manufacturing a longitudinallyexpandable plastic bottle according to claim 7, wherein said methodcomprises a step of charging contents, in which said bottle in the statein which said bellows shaped portion is collapsed in a lapped manner istransported to a contents charging plant where said bottle is filledwith contents, and air is blown to expand said bottle before saidcontents are charged, or said bottle is restored to the original statebefore being collapsed under a pressure of contents charged.
 27. Themethod for manufacturing a longitudinally expandable plastic bottleaccording to claim 14, wherein said method comprises a step of chargingcontents, in which said bottle in the state in which said bellows shapedportion is collapsed in a lapped manner is transported to a contentscharging plant where said bottle is filled with contents, and air isblown to expand said bottle before said contents are charged, or saidbottle is restored to the original state before being collapsed under apressure of contents charged.
 28. The method for manufacturing alongitudinally expandable plastic bottle according to claim 11, whereinsaid method comprises a step of charging contents, in which said bottlein the state in which said bellows shaped portion is collapsed in alapped manner is transported to a contents charging plant where saidbottle is filled with contents, and air is blown to expand said bottlebefore said contents are charged, or said bottle is restored to theoriginal state before being collapsed under a pressure of contentscharged.
 29. The method for manufacturing a longitudinally expandableplastic bottle according to claim 22, wherein said method comprises astep of charging contents, in which said bottle in the state in whichsaid bellows shaped portion is collapsed in a lapped manner istransported to a contents charging plant where said bottle is filledwith contents, and air is blown to expand said bottle before saidcontents are charged, or said bottle is restored to the original statebefore being collapsed under a pressure of contents charged.
 30. Themethod for manufacturing a longitudinally expandable plastic bottleaccording to claim 23, wherein said method comprises a step of chargingcontents, in which said bottle in the state in which said bellows shapedportion is collapsed in a lapped manner is transported to a contentscharging plant where said bottle is filled with contents, and air isblown to expand said bottle before said contents are charged, or saidbottle is restored to the original state before being collapsed under apressure of contents charged.
 31. The method for manufacturing alongitudinally expandable plastic bottle according to claim 24, whereinsaid method comprises a step of charging contents, in which said bottlein the state in which said bellows shaped portion is collapsed in alapped manner is transported to a contents charging plant where saidbottle is filled with contents, and air is blown to expand said bottlebefore said contents are charged, or said bottle is restored to theoriginal state before being collapsed under a pressure of contentscharged.
 32. The method for manufacturing a longitudinally expandableplastic bottle according to claim 5, wherein the step of compressionmolding of said bottle is performed while air in said bottle is sucked.33. The method for manufacturing a longitudinally expandable plasticbottle according to claim 7, wherein the step of compression molding ofsaid bottle is performed while air in said bottle is sucked.
 34. Themethod for manufacturing a longitudinally expandable plastic bottleaccording to claim 14, wherein the step of compression molding of saidbottle is performed while air in said bottle is sucked.
 35. The methodfor manufacturing a longitudinally expandable plastic bottle accordingto claim 11, wherein the step of compression molding of said bottle isperformed while air in said bottle is sucked.
 36. The method formanufacturing a longitudinally expandable plastic bottle according toclaim 22, wherein the step of compression molding of said bottle isperformed while air in said bottle is sucked.
 37. The method formanufacturing a longitudinally expandable plastic bottle according toclaim 23, wherein the step of compression molding of said bottle isperformed while air in said bottle is sucked.
 38. The method formanufacturing a longitudinally expandable plastic bottle according toclaim 24, wherein the step of compression molding of said bottle isperformed while air in said bottle is sucked.